GEOLOGY. 289 



great area of this formation are of great importance, as all the metalliferous 

 veins hitherto discovered in Auckland, or likely to be found, occur in rocks 

 of this formation. To these rocks belong the copper pyrites, which have 

 been worked for sonic years, the manganese, and the gold-bearing quartz at 

 Coromandcl. The gold which is washed out from beds of quartz-gravel, on 

 both sides of the Coromandel range, is derived from quartz-veins of crystal- 

 line character and considerable thickness, running in a general direction, 

 from north to south, through the old primary rocks which form the founda- 

 tion of the Coromandcl range. The coal-beds at Coromandel, occurring 

 between strata of trachytic breccia, arc too thin to be of any value, and there 

 is no reason to suppose that a workable scam exists. Nearly all the primary 

 ranges arc covered with dense virgin forests, rendering them extremely diffi- 

 cult of access; but there is every reason to believe that they will yield con- 

 siderable mineral riches. It is remarkable, that while one of the oldest 

 members of the primary formation is found so extensively in New Zealand, 

 the later strata of the Devonian, Carboniferous, and Permian systems, appear 

 to be altogcter wanting; while, on the other hand, in the neighboring con- 

 tinent of Australia, these members of the primary period, together with 

 plutonic and metamorphic rocks, constitute, so far as we know, almost the 

 principal part of the continent. A very wide interval occurs between the 

 primary rocks of the northern island, and the next sedimentary strata. Not 

 only the upper members of the primary series are absent, but also nearly the 

 whole of the secondary formations. The only instance of secondary strata 

 met with by Dr. Hochstetter, consists of a very regular and highly-inclined 

 bed of marl, alternating with micaceous sandstone, extending to a thickness 

 of more than one thousand feet. These rocks contain remarkable specimens 

 of marine fossils, which belong exclusively to the secondary period. The 

 tertiary period must be divided into two distinct formations which may, per- 

 haps, correspond to the European eocene and mioccnc. The older of these 

 formations contains the brown-coal seams, on the skilful working of which 

 mii'-h of the future welfare of the province depends. 



Dr. Hochstetter explored the remarkable limestone caverns at Hangatiki, 

 near the sources of the Waipa, the former haunts of the gigantic Moa. He 

 expected to meet with a rich harvest of Moa skeletons, but only found a few 

 bones. The natives, according to his account, have long since carefully 

 collected and stowed away, in safe hiding-places, all the Moa bones, in con- 

 sequence of the value attached to them by Europeans; but they are willing 

 to exchange them for money. 



The volcanic formations in Xew Zealand are on a vast scale. Lofty tra- 

 chytic peaks, covered with perpetual snow; a great variety of smaller volcanic 

 cones, presenting all the characteristics of volcanic systems; and long lines 

 of boiling springs, fumaroles, and solfataras, present an almost unbounded 

 field of interest, and, at the same time, a succession of magnificent scenery. 



The first volcanic eruptions were submarine, consisting of vast quantities 

 of lava, breccia, tuff, obsidian, and pumice-stone, which, flowing over the 

 bottom of the sea, formed an extensive submarine volcanic plateau. Subse- 

 quent eruptions formed lofty cones of trachytic and phonolithic lava, Thus, 

 in the central part of the northern island, an extensive volcanic plateau 

 exists, two thousand feet high, from which rise the two gigantic mountains, 

 Tonirariro and Ruapahu. From the former, smoke constantly issues, and 

 the shape of the cone is changing, thus showing continual volcanic activity. 

 A grand impression is made upon the traveller by these two magnificent 



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